Not sure what your car needs?

Manage your car online

Q:
high idle when hot and missfire all the time.

asked by
Sam K
on
April 24, 2016

so I replaced a blown head gasget and now I know I timed it correctly but I put it back together and now I am getting check engine code p0300,p0301,p0303 I see white smoke out of the muffler and it smells of burnt oil and idles at 2000rpms and has a missing fire sound. when cold not as often misfire sound and 800rpm idle. I checked the pcv valve and it is fine. its not getting hot. idk what to do? thanks.

My car has 207000 miles.
My car has an automatic transmission.

Services recommended for this issue

Enter your car for a more accurate estimate

If you overheated the engine prior to replacing the head gasket you would need to have the head checked for cracks and get the surface refaced. If this has been done, then the problem may be that the cylinder block is cracked, or you have not put something together properly and have a vacuum leak. The left over coolant in the exhaust from the previous overheating may be the reason for the smoke which will eventually go away.

Check the cooling system and engine for overheating again, if so, then you will need to find where the coolant is getting into the cylinders. A certified mechanic would be able to diagnose the symptoms you’ve described to in order to fix your misfire and high idle issues.

Get an instant quote for your car

What others are asking

Q: What does the information display tell you?

The information display on your dash gives you access to critical information. You can cycle through each readout and adjust some of these as well. Here’s what you need to know: Odometer: The odometer tells you how many miles...

Hello. Depending on why the Check Engine Light is still coming on would determine if it is safe to drive it. If you are getting codes related to the oxygen sensors and the catalytic converter then you may have the...

Q: What information is shown in the information display?

The following information is shown on the information display: Vehicle mileage (total mileage for the vehicle) Trip meter A (this can be reset at any point to track mileage) Trip meter B (this can be reset at any point...